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101.
BACKGROUND: Up to 20 million persons are infected with the human retroviruses human T-lymphotropic virus (HTLV)-I and HTLV-II globally. Most data on the seroprevalence of HTLV-I and HTLV-II in Europe are from studies of low-risk blood donors or high-risk injection drug users (IDUs). Little is known about the general population. METHODS: A prospective anonymous study of HTLV-I and HTLV-II seroprevalence among 234,078 pregnant women in Belgium, France, Germany, Italy, Portugal, Spain, and the United Kingdom was conducted. Maternal antibody status was determined by standard methods using sera obtained for routine antenatal infection screens or eluted from infant heel prick dried blood spots obtained for routine neonatal metabolic screens. RESULTS: Anti-HTLV-I/II antibodies were detected and confirmed in 96 pregnant women (4.4 per 10,000, 95% confidence interval [CI]: 3.5-5.2). Of these, 73 were anti-HTLV-I, 17 were anti-HTLV-II, and 6 were specifically anti-HTLV but untyped. The seroprevalence ranged from 0.7 per 10,000 in Germany to 11.5 per 10,000 in France. CONCLUSIONS: Pregnant women better reflect the general population than blood donors or IDUs. The seroprevalence of HTLV-I and HTLV-II in Western Europe is 6-fold higher among pregnant women (4.4 per 10,000) than among blood donors (0.07 per 10,000). These data provide a robust baseline against which changes in HTLV-I and HTLV-II seroprevalence in Europe can be measured.  相似文献   
102.
The distribution and metabolism of ACTH and the dynamics of the adrenal cortical response to this tropic hormone were characterized in the rat, through mathematical models involving data derived from experiments, where plasma corticosterone concentrations were measured following both single injections and infusions of ACTH. The models, which incorporate a previously established model of the dynamics of plasma corticosterone, were statistically validated. The simulated dynamics of the different processes linking ACTH secretion by the adenohypophysis to corticosterone secretion by the adrenal cortex include: (1) a variable MCR for plasma ACTH, modeled as the sum of a constant and a saturable degradation process; (2) the ability of the adrenal gland to secrete at a maximal rate aven after the plasma ACTH concentration has become negligible, modeled as the accumulation of an intermediary productZ directly controlled by the plasma ACTH concentration; (3) a saturable secretion with a small time constant and which, for single injections, always starts in the same fashion, modeled as a “synthesis process” whose input is a saturable function ofZ; (4) an immediate fall of the plasma corticosterone concentration at the end of the ACTH infusions, modeled as a “release process” also controlled byZ. Supported by grants from the Medical Research Council of Canada (MT-1205, MT-1555, and MA-4970), and from INSERM, France (CRL-76-5-020-4).  相似文献   
103.
Human herpesvirus-8 (HHV-8) causes Kaposi's sarcoma (KS) and lymphoproliferative disorders in both HIV-infected and uninfected patients. HHV-8 has a worldwide occurrence but infection rates vary according to a combination of geographic and behavioral risks. The main transmission route seems to be sexual, nevertheless, nasal secretions, saliva, blood, and organ graft have been proposed. HHV-8 was postulated as a new infectious agent for screening in blood donors. The aim of this study was to evaluate the prevalence of antibodies against HHV-8 antigens in blood donors of South America. Serum samples from 2,470 blood donors from Argentina, Brazil, and Chile corresponding to five geographic regions were studied by indirect immunofluorescence assay (IFA). Seroprevalence rate was 3.7% (92/2,470; 95% CI 2.9-4.5) in the entire blood donor population distributed as follows: Argentina, 4.0% (Buenos Aires city, 4.3%; Bahia Blanca, 2.4%; and Córdoba, 4.0%), Campinas (Brazil), 2.8%; and Santiago de Chile, 3.0%. There was no difference (P>0.05) between men and women or age related, except in Brazil where positive cases were 30-49-year-old males. The present study, which includes different geographical areas of multiple countries from South America, has not been done before. The results show similar prevalence rates among the studied zones corresponding to low-prevalence regions. South America is a large sub-continent with a wide spectrum of population and geographical characteristics, thus, more HHV-8 prevalence studies should be necessary to establish possible regional differences.  相似文献   
104.
In this study, we analyzed the antimicrobial resistance properties and T antigenic types of 511 isolates collected in Lisbon district, Portugal, from throat swabs of healthy subjects (n=341), during 2000-2002 and from diverse infection sites (n=170) of outpatients and inpatients, during 1999-2002. Erythromycin resistance was higher in tonsillitis/pharyngitis (27.4%) and skin infection isolates (21.1%), than in carriage and invasive isolates (相似文献   
105.
A total of 431 consecutive patients from the Midi Pyrenees area with acute hepatitis with unknown etiology in 2001-2002 were tested for the presence of immunoglobulin G-class (IgG) anti-hepatitis E virus (HEV) antibodies. Forty-six (10.7%) had anti-HEV IgG, and the results were questionable for a further 17 (3.9%). Real time PCR based on TaqMan detection was used to identify HEV genome fragments in the serum of patients with positive or questionable anti-HEV serology. HEV RNA was found in 25.4% of cases. All amplification products were sequenced and analyzed. Phylogenetic analysis revealed that all the strains were genotype 3. In conclusion, virological and epidemiological data indicate that genotype 3 viruses are circulating in the south west part of France (Midi-Pyrenees) in patients with acute hepatitis and who have not visited recently areas in which HEV is endemic.  相似文献   
106.
Individual sperm from men with balanced translocations have different chromosomal contents. Thus, an estimation of the overall sperm chromosomal imbalance of such patients could help to give the couple an adapted genetic counselling. We report here the study of a balanced translocation carrier, t(17;22) (q11;q12) whose reproductive history reported four miscarriages. Moreover, he had an abnormal semen analysis with oligoteratozoospermia. The meiotic segregation pattern was examined in 700 sperm, using fluorescence in-situ hybridization (FISH). Nineteen percent of the sperm had balanced translocations or were normal. All other sperm were unbalanced (81%) and their distribution was observed as follows: the frequencies of adjacent 1, adjacent 2 and 3:1 segregations were 12.9, 5.8 and 46.8% respectively. Among the segregations scored, 13.7% were related to second meiotic division abnormalities. Less than 2% of the total sperm scored were not explained. The 3:1 segregation was present at a very high rate, which is very unusual. In cases of balanced translocations, we believe that no general features can be drawn. Thus, the FISH technique may be very helpful for genetic counselling, which remains an important step and must be done with care.  相似文献   
107.
This report describes a family with mental retardation in two brothers. The pedigree is consistent with either X-linked mental retardation or autosomal recessive inheritance. The clinical features consist of coarse face, prominent lower lip, large testes, and obesity. This same constellation of findings was observed in a family with X-linked mental retardation (XLMR) reported by Shashi et al. [2000: Am J Hum Genet 66:469-479]. Furthermore, haplotype analysis was consistent with localization of the Shashi XLMR syndrome in Xq26-q27. Thus, the family likely represents a second occurrence of the Shashi XLMR syndrome.  相似文献   
108.
Inverted 'flying" exercise with external loads of 25, 50, 75 and 100% of each individual maximum load in the pectoralis major and deltoideus anterior muscles was electromyographically analyzed in eleven male volunteers, using surface electrodes MEDI-TRACE-200 connected to a biological signals acquisition module coupled to a PC/AT computer. Electromyographic signals were processed and the effective values obtained were standardized through maximum voluntary isometric contraction. When the concentric phase of each muscle with the same load was statistically compared with the eccentric phase, it was observed that for all loads all the muscles presented significant electromyographic difference, and that the concentric phase was always higher. By analyzing the different loads for each muscle, it was noticed that in the concentric phase all the muscles presented significant electromyographic activity, being it higher with maximum load. When the effect of each load on different muscle in the concentric and eccentric phases was analyzed, the muscles presented a distinct activity profile.  相似文献   
109.
The OPA1 gene, encoding a dynamin-related GTPase that plays a role in mitochondrial biogenesis, is implicated in most cases of autosomal dominant optic atrophy (ADOA). Sixty-nine pathogenic OPA1 mutations have been reported so far. Most of these are truncating mutations located in the GTPase domain coding region (exons 8-16) and at the 3'-end (exons 27-28). We screened 44 patients with typical ADOA using PCR-sequencing. We also tested 20 sporadic cases of bilateral optic atrophy compatible with ADOA. Of the 18 OPA1 mutations found, 14 have never been previously reported. The novel mutations include one nonsense mutation, 3 missense mutations, 6 deletions, one insertion and 3 exon-skipping mutations. Two of these are de novo mutations, which were found in 2 patients with sporadic optic atrophy. The recurrent c.2708_2711delTTAG mutation was found in 2 patients with a severe congenital presentation of the disease. These results suggest that screening for OPA1 gene mutations may be useful for patients with optic atrophy who have no affected relatives, or when the presentation of the disease is atypical as in the case of early onset optic atrophy.  相似文献   
110.
Two monoclonal antibodies (mAbs) raised against the macrogamonts of Eimeria tenella identified antigens located in the wall-forming bodies of type I (WF I) and type II (WF II) by indirect immunofluorescence and by immunoelectron microscopy. With these mAbs, the involvement of both types of wall-forming body at the protein level in the formation of the inner and outer oocyst walls of E. tenella was shown by indirect immunofluorescence assay. On Western blots of pure macrogamont, mAb E1D8 against WF I reacted with a series of bands between 42 kDa and 105 kDa. In pure, unsporulated extract, this mAb recognized a complex of bands between 26 kDa and 153 kDa. mAb E2E5 against WF II, on Western blots of pure extract of macrogamonts, recognized an antigen of 51 kDa. Later in the development, after the formation of the inner oocyst wall, mAb E2E5 reacted with three polypeptide of 23, 25 and 30 kDa. Proteolytic processing may be forwarded as the mechanism regulating the distinct regulation protein involved in the oocyst wall.  相似文献   
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